The present invention relates to lawn mower blades and particularly to mulching blades for rotary lawn mowers.
Until recent times, most owners of lawn tractors and walk-behind mowers preferred to collect the grass clippings as they mowed.
It has now been recognized that these clippings represent a substantial burden on the capacity of landfills and other disposal means. In some areas, legislation has been passed that forbids the deposition of clippings in landfills.
Because of these factors and a general increase in environmental awareness, many owners now wish to leave the clippings where they fall.
Unfortunately, this may result in unattractive debris clearly overlaying the lawn, which in some cases may actually damage the lawn. To help minimize this, specialized mulching mowers have been proposed.
These mowers tend to be expensive and are typically ill-suited to be used as a conventional mower should the need arise (e.g., unusually high and/or wet grass).
To provide an alternative to specialized mowers, various mulching blades have been proposed for use in a conventional mower. The main purpose of these blades is to cut the grass fine enough to allow the debris to find its way down to the soil level where it forms a mulch.
While almost any blade will prove adequate if only a short length of un-wetted grass is cut, it has been difficult to produce clippings that are both properly comminuted and evenly spread or "hidden" when more typical conditions are encountered.
It has been particularly difficult to achieve satisfactory hiding of the clippings.